Substituted 1-arylpyrazoles

ABSTRACT

The invention relates to new substituted 1-arylpyrazoles of the general formula (I)                    
     to a plurality of processes for their preparation, and to their use as pesticides.

The invention relates to new substituted 1-arylpyrazoles, to a pluralityof processes for their preparation, and to their use as pesticides.

It has already been disclosed that certain substituted 1-arylpyrazoles,such as, for example,5-amino-1-[2,6-dichloro-4-(trifluoromethyl)-phenyl]-3-cyano-4-[(trifluoromethyl)-sulphinyl]-1H-pyrazole,have a good activity against pests (cf. for example EP-A 295 117 andEP-A 352 944).

Moreover, a large number of substituted 1-arylpyrazoles are describedwhich can be employed for combating pests (cf. for example EP-A 201 852,EP-A 418 016).

In addition, substituted 1-arylpyrazoles are also used as intermediatesfor the preparation of pesticides (cf. for example EP-A 301 338, EP-A301 339, EP-A 374 061, EP-A 260 521).

However, the level and duration of action of the previously knowncompounds is not entirely satisfactory in all fields of application, inparticular in the case of certain insects or when low applicationconcentrations are used.

New substituted 1-arylpyrazoles of the general formula (I)

in which

R¹ represents hydrogen, cyano, alkyl, alkoxyalkyl, alkylthioalkyl,halogenoalkyl or cyanoalkyl,

R² represents difluoroethyl or trifluoroethyl,

R³ represents hydrogen, amino, halogen or one of the following groups

in which

R⁴ represents alkyl, halogenoalkyl, alkoxyalkyl or optionallysubstituted phenyl,

R⁵ represents hydrogen or alkyl,

R⁶ represents hydrogen, alkyl or optionally substituted phenyl and

R⁷ represents alkyl or

R⁵ and R⁶ together with the carbon atom to which they are bondedrepresent an optionally substituted heterocycle,

Ar represents optionally substituted phenyl or pyridyl and

n represents a number 0, 1 or 2,

have now been found.

Furthermore, it has been found that the new substituted 1-arylpyrazolesof the general formula (I) are obtained by one of the processesdescribed below:

a) Substituted 1-aryl-4-mercapto-pyrazoles of the formula (Ia)

in which

R¹, R², Ar and n have the abovementioned meaning and R³⁻¹ representshydrogen or amino, are obtained when pyrazole derivatives of the formula(II)

in which

R¹, R³⁻¹ and Ar have the abovementioned meanings, are reacted withsulphenyl halides of the formula (III)

R²—S—Hal   (III)

in which

R² has the abovementioned meaning and Hal represents halogen, inparticular chlorine or bromine,

if appropriate in the presence of a diluent and if appropriate in thepresence of a reaction auxiliary.

b) Substituted 1-arylpyrazoles of the formula (Ib)

in which

R¹, R², R³⁻¹ have the abovementioned meanings and

n represents the number 1 or 2,

are obtained when compounds of the formula (Ia)

in which

R¹, R² and R³⁻¹ have the abovementioned meanings,

are oxidized using oxidants, if appropriate in the presence of a diluentand if appropriate in the presence of a catalyst.

Other preparation methods for the compounds of the formula (I) accordingto the invention are given hereinbelow by way of example, but not bylimitation, R¹, R², R⁴, R⁵, R⁶, R⁷, Ar and n having the abovementionedmeaning:

c) Reaction of substituted 1-arylpyrazoles of the formula (Ic)(R³⁻¹=NH₂) with acid halides of the formula (IV) (Hal=chlorine):

d) Reaction of substituted 1-arylpyrazoles of the formula (Ic)(R³⁻¹=NH₂) with acetals of the formula (V) (R⁸=alkyl):

e) Reaction of substituted 1-arylpyrazoles of the formula (Ic)(R³⁻¹=NH₂) with tetrahydrofuran derivatives of the formula (VI)(R⁸=alkyl):

f) Reaction of substituted 1-arylpyrazoles of the formula (Ic)(R³⁻¹=NH₂) with aldehydes or ketones of the formula (VII):

g) Reaction of substituted 1-arylpyrazoles of the formula (Ic)(R³⁻¹=NH₂) with ortho esters of the formula (VIII):

h) Reaction of substituted 1-arylpyrazoles of the formula (Ic)(R³⁻¹=NH₂) with tribromomethane, of the formula (IX):

i) Reaction of Substituted 1-arylpyrazoles of the formula (Ic)(R³⁻¹=NH₂) with nucleophiles NU:

The invention preferably relates to compounds of the formula (I) inwhich

R¹ represents hydrogen, cyano, (C₁-C₆)-alkyl,(C1-C4)-alkoxy-(C₁-C₄)-alkyl, (C₁-C₄) -halogenoalkyl or(C₁-C₂)-cyanoalkyl,

R² represents difluoroethyl or trifluoroethyl,

R³ represents hydrogen, amino, halogen or one of the following groups

in which

R⁴ represents (C₁-C₆)-alkyl, (C₁-C₆)-halogenoalkyl having 1-3 halogenatoms, (C₁-C₆)-alkoxy-(C₁-C₆)-alkyl, or phenyl which is optionallymonosubstituted to trisubstituted by identical or differentsubstituents,

R⁵ represents hydrogen or (C₁-C₆)-alkyl,

R⁶ represents hydrogen, (C₁-C₆)-alkyl, or phenyl which is optionallymonosubstituted to trisubstituted by identical or differentsubstituents,

R⁷ represents (C₁-C₆)-alkyl or

R⁵ and R⁶ together with the carbon atom to which they are bondedrepresent optionally substituted pyridyl,

Ar represents phenyl or pyridyl, each of which is optionallymonosubstituted to trisubstituted by identical or different substituentsfrom the series comprising halogen, halogeno (C₁-C₆)alkyl,halogeno(C₁-C₆)alkylthio, halogeno(C₁-C₆)alkoxy, alkoxy, hydrazino,(C₁-C₆)-dialkylhydrazino, amino, amino(C₁-C₆)alkyl, diamino(C₁-C₆)alkyl,imino(C₁-C₆)-alkyl, cyano, (C₁-C₆)alkylthio or the group

in which

R⁹ and R¹⁰ are identical or different and represent hydrogen or(C₁-C₆)-alkyl, and

n represents a number 0, 1 or 2.

In particular, the invention relates to compounds of the formula (I) inwhich

R¹ represents hydrogen, cyano, (C₁-C₄)-alkyl,(C₁-C₄)-alkoxy-(C₁-C₂)-alkyl, (C₁-C₂)-halogenoalkyl having 1 to 5identical or different fluorine, chlorine or bromine atoms, orcyanomethyl,

R² represents difluoroethyl or trifluoroethyl,

R³ represents hydrogen, amino, bromine or one of the following groups

in which

R⁴ represents (C₁-C₄)-alkyl, (C₁-C₄)-halogenoalkyl having 1-3 halogenatoms, (C₁-C₄) -alkoxy-(C₁-C₂)-alkyl, or phenyl which is optionallymonosubstituted to trisubstituted by identical or differentsubstituents,

R⁵ represents hydrogen or (C₁-C₄)-alkyl,

R⁶ represents hydrogen, (C₁-C₄)-alkyl, phenyl which is optionallymonosubstituted or disubstituted by identical or different substituents,or 4-hydroxy-3-methoxy-phenyl,

R⁷ represents (C₁-C₄)-alkyl or

R⁵ and R⁶ together with the carbon atom to which they are bondedrepresent optionally substituted pyridyl,

Ar represents phenyl or pyridyl, each of which is optionallymonosubstituted to trisubstituted by identical or different substituentsfrom the series comprising fluorine, chlorine, trifluoromethyl,trifluoromethylthio, trifluoromethoxy, methoxy, hydrazino,dimethylhydrazino, amino, methylamino, dimethylamino, iminomethyl,cyano, methylthio or the group

in which

R⁹ and R¹⁰ are identical or different and represent hydrogen or(C₁-C₄)-alkyl, and

n represents a number 0, 1 or 2.

Very particularly preferred compounds of the formula (I) are those inwhich

R¹ represents hydrogen, cyano, (C₁-C₄)-alkyl, methoxymethyl,ethoxymethyl, methoxyethyl, ethoxyethyl, trifluoromethyl, bromomethyl orcyanomethyl,

R² represents 1,1-difluoroethyl or 2,2,2-trifluoroethyl,

Ar represents phenyl which is disubstituted or trisubstituted byidentical or different substituents, substituents in the 2-positionbeing fluorine or chlorine, in the 4-position trifluoromethyl and in the6-position fluorine, chlorine, cyano, methoxy, methylthio,trifluoromethyl, trifluoromethoxy or trifluoromethylthio, or

Ar represents a 2-pyridyl radical which is substituted in the 4-positionby trifluoromethyl and in the 6-position by fluorine or chlorine, and

R³ and n have the abovementioned meanings.

The abovementioned general definitions or those where preferred rangeshave been mentioned apply to the end products of the formula (I) and,analogously, to the starting materials or intermediates required in eachcase for the preparation. The definitions can be combined with eachother, that is to say any desired combinations between the preferredranges indicated are possible.

The hydrocarbon radicals mentioned in the definition of the radicals,such as alkyl, alkoxy, alkoxyalkyl and alkylthio, are straight-chain orbranched, even if this is not stated expressly.

Halogen generally represents fluorine, chlorine, bromine or iodine,preferably fluorine, chlorine or bromine, in particular fluorine orchlorine.

The following substituted 1-arylpyrazoles of the general formula (I) maybe mentioned individually in addition to the compounds mentioned in thePreparation Examples:

TABLE 1 (I)

R¹ R² R³ n Ar H CF₂CH₃ NH₂ 0

CH₂Br CH₂CF₃ NH₂ 0

CH₂Br CF₂CH₃ NH₂ 0

CH₃OCH₂ CF₂CH₃ NH₂ 1

CH₃OCH₂ CF₂CH₃ NH₂ 2

CH₃OCH₂ CF₂CH₃ NH₂ 1

CH₃OCH₂ CF₂CH₃ NH₂ 2

CH₃OCH₂ CH₂CF₃ NH₂ 2

CH₃OCH₂ CH₂CF₃ NH₂ 1

CN CF₂CH₃ NH₂ 1

CN CH₂CF₃ NH₂ 1

H CF₂CH₃ NH₂ 1

H CF₂CH₃ NH₂ 2

H CF₂CH₃ NH₂ 1

H CF₂CH₃ NH₂ 2

H CF₂CH₃ NH₂ 2

H CH₂CF₃ NH₂ 1

H CH₂CH₃ NH₂ 2

CH₃ CF₂CH₃ NH₂ 2

CH₃ CF₂CH₃ NH₂ 1

CH₃ CH₂CF₃ NH₂ 1

If, for example,5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-methyl-pyrazole and1,1-difluoroethylsulphenyl chloride are used as starting substances, thecourse of the reaction of process (a) according to the invention can berepresented by the following equation:

If, for example,5-amino-3-methoxymethyl-4-(2,2,2-trifluoromethylthio)-1-[(3-chloro-5-trifluoromethyl)-2-pyridyl]-pyrazoleis used as starting substance, H₂O₂ as oxidant and sodium tungstate ascatalyst, the course of the reaction of process (b) according to theinvention can be represented by the following equation:

If, for example,5-amino-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethyl-phenyl)-3-methoxymethylpyrazoleand methoxyacetyl chloride are used as starting substances, the courseof the reaction of process (c) according to the invention can berepresented by the following equation:

If, for example,5-amino-3-cyano-4-(1,1-difluoroethylthio)-1-thio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleand dimethylformamide dimethyl acetal are used as starting substances,the course of the reaction of process (d) according to the invention canbe represented by the following equation:

If, for example, 5-amino-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethyl-phenyl)-pyrazole and2,5-dimethoxytetrahydrofuran are used as starting substances, the courseof the reaction of process (e) according to the invention can berepresented by the following equation:

If, for example,5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-methyl-4-(1,1-difluoroethylthio)-pyrazoleand 3-methoxy-4-hydroxybenzaldehyde are used as starting substances, thecourse of the reaction of process (f) according to the invention can berepresented by the following equation:

If, for example,5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-methyl-4-(1,1-difluoroethylthio)-pyrazoleand ethyl orthoformate are used as starting substances, the course ofthe reaction of process (g) according to the invention can berepresented by the following equation:

If, for example,5-amino-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazole,tribromomethane and tert-butyl nitrite are used as starting substances,the course of the reaction of process (h) according to the invention canbe represented by the following equation:

If, for example,5-amino-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleand hydrazine hydrate are used as starting substances, the course of thereaction of process (i) according to the invention can be represented bythe following equation:

Some of the pyrazole derivatives of the formula (II) to be used asstarting substances for carrying out process (a) according to theinvention are known, or they can be obtained by known processes (cf. forexample EP-A 295 117, EP-A 154 115, EP-A 201 852).

The pyrazole derivatives of the formula (IIa)

in which

R³⁻¹ and Ar have the abovementioned meaning, are new and a subject ofthe invention.

The compounds of the formula (IIa) can be obtained by generallycustomary and known processes by heating bromomethyl-pyrazoles of theformula (IIb)

in which

R³⁻¹ and Ar have the abovementioned meaning, together with alkali metalcyanides, such as, for example, sodium cyanide or potassium cyanide, ifappropriate in the presence of an inert diluent, such as, for example,water, and in the presence of a phase transfer catalyst, such as, forexample, TEBA, at temperatures between 40° C. and 100° C., preferably70° C. to 100° C. (cf. Preparation Example).

If, for example,5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-bromomethyl-pyrazoleis used as starting substance and an aqueous sodium cyanide solution andTEBA as phase transfer catalyst, the course of the reaction of theprocess according to the invention can be represented by the followingequation:

The bromomethylpyrazoles of the formula (IIb), which are required asstarting compounds for the preparation of the pyrazole derivatives ofthe formula (IIa), are new and a subject of the invention.

Compounds of the formula (IIb) are obtained by generally customary andknown processes by heating methoxymethylpyrazoles of the formula (IIc):

in which

R³⁻¹ and Ar have the abovementioned meaning, together with a 48%strength solution of hydrogen bromide in glacial acetic acid attemperatures between 60° C. and 130° C., preferably at temperaturesbetween 90° C. and 130° C. (cf. Preparation Examples).

If, for example,5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-methoxypyrazole and48% strength solution of hydrogen bromide in glacial acetic acid areused as starting substances, the course of the reaction of the processaccording to the invention can be represented by the following equation:

The methoxymethylpyrazoles of the formula (IIc), which are required asstarting compounds for the preparation of the bromomethylpyrazolederivatives of the formula (IIb), are new and also a subject of theinvention.

The compounds of the formula (IIc) can be obtained by heatingarylhydrazines of the formula (X)

Ar—NHNH₂   (X)

in which

Ar has the abovementioned meaning, together with2-amino-1-cyano-3-methoxy-propene of the formula (XI)

if appropriate in the presence of an inert organic solvent, such as, forexample, alcohols, preferably methanol or ethanol, or acetic acid, ormixtures of methanol and acetic acid or ethanol and acetic acid, attemperatures between 50° C. and 130° C., preferably 60° C. and 120° C.To carry out the process, 1 to 4 mol, preferably 1 to 2 mol, of1-cyano-2-amino-3-methoxy-propene of the formula (XI) is generallyemployed per mole of arylhydrazine of the formula (X) . The reaction iscarried out and the compounds of the formula (IVc) are worked up andisolated in the customary manner.

If, for example, 2,6-dichloro-4-trifluoromethylphenylhydrazine and1-cyano-2-amino-3-methoxy-propene are used as starting substances, thecourse of the reaction of the process according to the invention can berepresented by the following equation:

The arylhydrazines of the formula (X) , which are required as startingsubstances, are generally known compounds of organic chemistry.

2-Amino-1-cyano-3-methoxypropene, of the formula (XI), which isfurthermore required for the preparation of the methoxymethylpyrazolesof the formula (IIc), is new and a subject of the invention.

2-Amino-1-cyano-3-methoxy-propene, of the formula (XI), is obtained whenmethoxyacetonitrile, of the formula (XII),

CH₃OCH₂—CN   (XII)

is heated together with acetonitrile and, if appropriate, in thepresence of an inert organic solvent, such as, for example, ethers,preferably diethyl ether, dibutyl ether, glycol dimethyl ether anddiglycol methyl ether, tetrahydrofuran and dioxane, or in mixtures ofacetonitrile and these solvents and in the presence of bases, such as,for example, sodium hydride or potassium tert-butylate, at temperaturesbetween 20° C. and 150° C., preferably 20° C. and 100 ° C. To carry outthe process, methoxyacetonitrile, the base in question and acetonitrileare generally employed in approximately-equimolar amounts. However, itis also possible to use one of the two components employed in each casein a larger excess. The reaction is carried out and the compounds of theformula (XI) are worked up and isolated in the customary manner (cf.Preparation Examples).

The compound of the formula (XI) can exist in the form of geometricisomers (E/Z isomers) or of variously composed mixtures of isomers. Theinvention claims the use of the pure isomers as well as of the isomermixtures. For simplicity's sake, the text hereinbelow will alwaysmention compounds of the formula (XI), even though this is to beunderstood as meaning the pure compounds and also their mixtures whichcontain various amounts of E/Z isomers.

Formula (III) provides a general definition of the sulphenyl halidesfurthermore required as starting substances for carrying out the process(a) according to the invention. In this formula (III), R² preferablyrepresents those radicals which have already been mentioned inconnection with the description of the substances of the formula (I)according to the invention as being preferred for this substituent.

The sulphenyl halides of the formula (III) are generally known compoundsof organic chemistry.

Formula (Ia) provides a general definition of the1-aryl-4-mercapto-pyrazoles required as starting substances for carryingout the process (b) according to the invention. In this formula (Ia),R¹, R², R³⁻¹ and Ar preferably represent those radicals and indiceswhich have already been mentioned in connection with the description ofthe substances of the formula (I) according to the invention as beingpreferred for these substituents.

The compounds of the formula (Ia) are compounds according to theinvention and can be obtained by process (a).

Formula (Ic) provides a general definition of the 1-aryl-4-pyrazolesrequired as Starting substances for carrying out the processes (c), (d),(e), (f), (g), (h) and (i) according to the invention. In this formula(Ic), R¹, R², Ar and n preferably represent those radicals and indiceswhich have already been mentioned in connection with the description ofthe substances of the formula (I) according to the invention as beingpreferred for these substituents.

The compounds of the formula (Ic) are compounds according to theinvention and can be obtained by processes (a) or (b).

The compounds of the formulae (IV), (V), (VI), (VII), (VIII) and (IX),which are furthermore required as starting compounds, are generallyknown compounds of organic chemistry.

Suitable nucleophiles (NuI) for carrying out the process (i) accordingto the invention are all customary reagents of organic chemistry whichare suitable for such reactions. Examples which may be mentioned, butnot by limitation, are: alcoholates, hydrazine derivatives and cyanides.

Suitable diluents for carrying out the process (a) according to theinvention are inert organic solvents. These include, in particular,aliphatic, alicyclic or aromatic, optionally halogenated hydrocarbons,such as, for example, benzine, benzene, toluene, xylene, chlorobenzene,petroleum ether, hexane, cyclohexane, dichloromethane, chloroform andcarbon tetrachloride; ethers, such as diethyl ether, dioxane,tetrahydrofuran or ethylene glycol dimethyl ether or ethylene glycoldiethyl ether, ketones, such as acetone or butanone, nitriles, such asacetonitrile or propionitrile; amides, such as dimethylformamide,dimethylacetamide, N-methylformanilide, N-methylpyrrolidone orhexamethylphosphoric triamide, esters, such as ethyl acetate,sulphoxides, such as dimethyl sulphoxide, or acids, such as, forexample, acetic acid.

If appropriate, process (a) according to the invention can be carriedout in the presence of a reaction auxiliary. Suitable reactionauxiliaries are all customary inorganic or organic bases. These include,for example, alkali metal hydroxides, such as sodium hydroxide orpotassium hydroxide, alkali metal carbonates, such as sodium carbonate,potassium carbonate or sodium hydrogen carbonate, and also tertiaryamines, such as triethylamine, N,N-dimethylaniline, pyridine,N,N-dimethylaminopyridine, diazabicyclooctane (DABCO),diazabicyclononene (DBN) or diazabicycloundecene (DBU).

When carrying out the process (a) according to the invention, thereaction temperatures can be varied within a substantial range. Ingeneral, the process is carried out at temperatures between −20° C. and+120° C., preferably at temperatures between 0° C. and +50° C.

For carrying out the process (a) according to the invention, 1.0 to 2.5mol, preferably 1.0 to 1.5 mol, of sulphenyl halide of the formula (III)and, if appropriate, 1.0 to 2.5 mol, preferably 1.0 to 1.5 mol, ofreaction auxiliary are generally employed per mole of pyrazolederivatives of the formula (II). The reaction is carried out and thereaction products of the formula (Ia) are worked up and isolated bygenerally customary processes.

Suitable oxidants for carrying out the process (b) according to theinvention are all customary oxidants which can be used for the oxidationof sulphur. Particularly suitable are hydrogen peroxide, organicperacids, such as, for example, peracetic acid, m-chloroperbenzoic acid,p-nitroperbenzoic acid or atmospheric oxygen.

Diluents which are suitable for carrying out the process (b) accordingto the invention are also inert organic solvents. The following arepreferably used: hydrocarbons, such as benzine, benzene, toluene, hexaneor petroleum ether; chlorinated hydrocarbons, such as dichloromethane,1,2-dichloroethane, chloroform, carbon tetrachloride or chlorobenzene;ethers, such as diethyl ether, dioxane or tetrahydrofuran; carboxylicacids, such as acetic acid or propionic acid, or dipolar aproticsolvents, such as acetonitrile, acetone, ethyl acetate ordimethylformamide.

If appropriate, process (b) according to the invention can be carriedout in the presence of an acid-binding agent. All organic and inorganicacid-binding agents which can conventionally be used are suitable. Thefollowing are preferably used: alkaline earth metal hydroxides, alkalineearth metal acetates, alkaline earth metal carbonates, alkali metalhydroxides, alkali metal acetates or alkali metal carbonates, such as,for example, calcium hydroxide, sodium hydroxide, sodium acetate orsodium carbonate.

If appropriate, process (b) according to the invention can be carriedout in the presence of a suitable catalyst. All metal salt catalystswhich are generally customary for such sulphur oxidations are suitable.Ammonium molybdate and sodium tungstate may be mentioned in this contextby way of example.

When carrying out the process (b) according to the invention, thereaction temperatures can be varied within a substantial range. Ingeneral, the process is carried out at temperatures between −20° C. and+70° C., preferably at temperatures between 0° C. and +50° C.

To carry out process (b) according to the invention, 0.8 to 1.2 mol,preferably equimolar amounts, of oxidant are generally employed per moleof substituted 1-arylpyrazole of the formula (Ia), if it is intended tointerrupt the oxidation of the sulphur at the sulphoxide level. 1.8 to3.0 mol, preferably twice the molar amounts, of oxidant are generallyemployed per mole of substituted 1-arylpyrazole of the formula (Ia) tooxidize the sulphoxide to the sulphone. The reaction is carried out andthe end products of the formula (Ib) are worked up and isolated bycustomary processes.

The active compounds are well tolerated by plants, have a favourabletoxicity to warm-blooded species and are suitable for combating animalpests, in particular insects, arachnids and nematodes, which occur inagriculture, in forests, in the protection of stored products and ofmaterials, and in the hygiene sector. They can preferably be used asplant protection agents. They are active .against normally sensitive andresistant species and against all or individual development stages. Theyabovementioned pests include:

From the order of the Isopoda, for example, Oniscus asellus,Armadillidium vulgate and Porcellio scaber.

From the order of the Diplopoda, for example, Blaniulus guttulatus.

From the order of the Chilopoda, for example, Geophilus carpophagus andScutigera spec.

From the order of the Symphyla, for example, Scutigerella immaculata.

From the order of the Thysanura, for example, Lepisma saccharina.

From the order of the Collembola, for example, Onychiurus armatus.

From the order of the Orthoptera, for example, Blatta orientalis,Periplaneta americana, Leucophaea maderae, Blattella germanlea, Achetadomesticus, Gryllotalpa spp., Locusta migratoria migratorioides,Melanoplus differentialis and Schistocerca gregaria.

From the order of the Dermaptera, for example, Forficula auricularia.

From the order of the Isoptera, for example, Reticulitermes spp.

From the order of the Anopolura, for example, Phylloxera vastatrix,Pemphigus spp., Pediculus humanus corporis, Haematopinus spp. andLinognathus spp., Bovicola spp.

From the order of the Mallophaga, for example, Trichodectes spp. andDamalinea spp.

From the order of the Thysanoptera, for example, Hercinothrips femoralisand Thrips tabaci.

From the order of the Heteroptera, for example, Eurygaster spp.,Dysdercus intermedius, Piestoa quadrata, Cimex lectularius, Rhodniusprolixus and Triatoma spp.

From the order of the Homoptera, for example, Aleurodes brassicae,Bemisia tabaci, Trialeurodes vaporariorum, Aphis gossypii, Brevicorynebrassicae, Cryptomyzus ribis, Doralis fabae, Doralis pomi, Eriosomalanigerum, Hyalopterus arundinis, Macrosiphum avenae, Myzus spp.,Photodon humuli, Rhopalosiphum padi, Empoasca spp., Euscelis bilobatus,Nephotettix cincticeps, Lecanium corni, Saissetia oleae, naodelphaxstriatellus, Nilaparvata lugens, Aonidiella aurantii, Aspidiotushederae, Psuedococcus spp. and Psylla spp.

From the order of the Lepidoptera, for example, Pectinophoragossypiella, Bupalus piniarius, Cheimatobia brumata, Lithocolletisblancardella, Hyponomeuta padella, Plutella maculipennis, Malacosomaneustria, Euproctis chrysorrhoea, Lymantria spp., Bucculatrixthurberiella, Phyllocnistis citrella, Agrotis spp., Euxoa spp., Feltiaspp., Earias insulana, Heliothis spp., Laphygma exigua, Mamestrabrassicae, Panolis flammea, Prodenia litura, Spodoptera spp.,Trichoplusia ni, Carpocapsa pomonella, Pieris spp., Chilo spp., Pyraustanubilalis, Ephestia kuehniella, Galleria mellonella, Tineolabisselliella, Tinea pellionella, Hofmannophila pseudospretella, Cacoeciapodana, Capua reticulana, Choristoneura fumiferana, Clysia ambiguella,Homona magnanima and Tortrix viridana.

From the order of the Coleoptera, for example, Anobium punctatum,Rhizopertha dominica, Bruchidius obtectus, Acanthoscelides obtectus,Hylotrupes bajulus, Agelastica alni, Leptinotarsa decemlineata, Phaedoncochleariae, Diabrotica spp., Psylliodes chrysocephala, Epilachnavarivestis, Atomaria spp., Oryzaephilus surinamensis, Anthonomus spp.,Sitophilus spp., Otiorrhynchus sulcatus, Cosmopolites sordidus,Ceuthorrhynchus assimilis, Hypera postica, Dermestes spp., Trogodermaspp., Anthrenus spp., Attagenus spp., Lyctus spp., Meligethes aeneus,Ptinus spp., Niptus hololeucus, Gibbium psylloides, Tribolium spp.,Tenebrio molitor, Agriotes spp., Conoderus spp., Melolontha melolontha,Amphimallon solstitialis and Costelytra zealandica.

From the order of the Hymenoptera, for example, Diprion spp., Hoplocampaspp., Lasius spp., Monomorium pharaonis and Vespa spp.

From the order of the Diptera, for example, Aedes spp., Anopheles spp.,Culex spp., Drosophila melanogaster, Musca spp., Fannia spp., Calliphoraerythrocephala, Lucilia spp., Chrysomyia spp., Cuterebra spp.,Gastrophilus spp., Hyppobosca spp., Stomoxys spp., Oestrus spp.,Hypoderma spp., Tabanus spp., Tannia spp., Bibio hortulanus, Oscinellafrit, Phorbia spp., Pegomyia hyoscyami, Ceratitis capitata, Dacus oleaeand Tipula paludosa.

From the order of the Siphonaptera, for example, Xenopsylla cheopis andCeratophyllus spp., Ctenocephalides spp.

From the order of the Arachnida, for example, Scorpio maurus andLatrodectus mactans.

From the order of the Acarina, for example, Acarus siro, Argas. spp.,Ornithodoros spp., Dermanyssus gallinae, Eriophyes ribis, Phyllocoptrutaoleivora, Boophilus spp., Rhipicephalus spp., Amhlyomma spp., Hyalommaspp., Ixodes spp., Psoroptes spp., Chorioptes spp., Sarcoptes spp.,Tarsonemus spp., Bryobia praetiosa, Panonychus spp. and Tetranychus spp.

The plant-parasitic nematodes include Pratylenchus spp., Radopholussimilis, Ditylenchus dipsaci, Tylenchulus semipenetrans, Heteroderaspp., Meloidogyne spp., Aphelenchoides spp., Longidorus spp., Xiphinemaspp. and Trichodorus spp.

The active compounds can be converted into the customary formulations,such as solutions, emulsions, suspensions, powders, foams, pastes,granules, aerosols, natural and synthetic materials impregnated withactive compound, very fine capsules in polymeric substances and incoating compositions for seed, and furthermore in formulations used withburning equipment, such as fumigating cartridges, fumigating cans,fumigating coils and the like, as well as ULV cold mist and warm mistformulations.

These formulations are produced in a known manner, for example by mixingthe active compounds with extenders, that is, liquid solvents, liquefiedgases under pressure, and/or solid carriers, optionally with the use ofsurface-active agents, that is, emulsifying agents and/or dispersingagents and/or foam-forming agents. In the case of the use of water as anextender, organic solvents can, for example, also be used as auxiliarysolvents. As liquid solvents, there are suitable in the main: aromatics,such as xylene, toluene or alkylnaphthalenes, chlorinated aromatics orchlorinated aliphatic hydrocarbons, such as chlorobenzenes,chloroethylenes or methylene chloride, aliphatic hydrocarbons, such ascyclohexane or paraffins, for example mineral oil fractions, alcohols,such as butanol or glycol as well as their ethers and esters, ketones,such as acetone, methyl ethyl ketone, methyl isobutyl ketone orcyclohexanone, strongly polar solvents, such as dimethylformamide anddimethyl sulphoxide, as well as water; by liquefied gaseous extenders orcarriers are meant liquids which are gaseous at ambient temperature andunder atmospheric pressure, for example aerosol propellants, such ashalogenohydrocarbons as well as butane, propane, nitrogen and carbondioxide; as solid carriers there are suitable: for example groundnatural minerals, such as kaolins, clays, talc, chalk, quartz,attapulgite, montmorillonite or diatomaceous earth, and ground syntheticminerals, such as highly-disperse silica, alumina and silicates; assolid carriers for granules there are suitable: for example crushed andfractionated natural rocks such as calcite, marble, pumice, sepioliteand dolomite, as well as synthetic granules of inorganic and organicmeals, and granules of organic material such as sawdust, coconut shells,maize cobs and tobacco stalks; as emulsifying and/or foam-forming agentsthere are suitable: for example non-ionic and anionic emulsifiers, suchas polyoxyethylene fatty acid esters, polyoxyethylene fatty alcoholethers, for example alkylaryl polyglycol ethers, alkylsulphonates, alkylsulphates, arylsulphonates as well as albumen hydrolysis products; asdispersing agents there are suitable: for example lignin-sulphite wasteliquors and methylcellulose.

Adhesives such as carboxymethylcellulose and natural and syntheticpolymers in the form of powders, granules or latices, such as gumarabic, polyvinyl alcohol and polyvinyl acetate, as well as naturalphospholipids, such as cephalins and lecithins, and syntheticphospholipids, can be used in the formulations. Other additives can bemineral and vegetable oils.

It is possible to use colorants such as inorganic pigments, for exampleiron oxide, titanium oxide and Prussian Blue, and organic dyestuffs,such as alizarin dyestuffs, azo dyestuffs and metal phthalocyaninedyestuffs, and trace nutrients such as salts of iron, manganese, boron,copper, cobalt, molybdenum and zinc.

The formulations in general contain between 0.1 and 95 percent by weightof active compound, preferably between 0.5 and 90%.

The active compounds according to the invention can be present in theircommercially available formulations and in the use forms, prepared fromthe formulations, as a mixture with other active compounds, such asinsecticides, attractants, sterilizing agents, acaricides, nematicides,fungitides, growth-regulating substances or herbicides. The insecticidesinclude, for example, phosphates, carbamates, carboxylates, chlorinatedhydrocarbons, phenylureas and substances produced by microorganisms.

The following compounds may be mentioned:

acrinathrin, alphamethrin, betacyfluthrin, bifenthrin, brofenprox,cis-resmethrin, clocythrin, cycloprothrin, cyfluthrin, cyhalothrin,cypermethrin, deltamethrin, esfenvalerate, etofenprox, fenpropathrin,fenvalerate, flucythrinate, fluvalinate, lambda-cyhalothrin, permethrin,pyresmethrin, pyrethrum, silafluofen, tralomethrin, zetamethrin,

alanycarb, bendiocarb, benfuracarb, bufencarb, butocarboxim, carbaryl,cartap, ethiofencarb, fenobucarb, fenoxycarb, isoprocarb, methiocarb,methomyl, metolcarb, oxamyl, pirimicarb, promecarb, propoxur, terbam,thiodicarb, thiofanox, trimethacarb, XMC, xylylcarb,

acephate, azinphos A, azinphos M, bromophos A, cadusafos,carbophenothion, chlorfenvinphos, chlormephos, chlorpyrifos,chlorpyrifos M, cyanophos, demeton M, demeton-S-methyl, demeton S,diazinon, dichlorvos, dicliphos, dichlorfenthion, dicrotophos,dimethoate, dimethylvinphos, dioxathion, disulfoton, edifenphos, ethion,etrimphos, fenitrothion, fenthion, fonophos, formothion, heptenophos,iprobenfos, isazophos, isoxathion, phorate, malathion, mecarbam,mevinphos, mesulfenphos, methacrifos, methamidophos, naled, omethoate,oxydemeton M, oxydeprofos, parathion A, parathion M, phenthoate,phorate, phosalone, phosmet, phosphamdon, phoxim, pirimiphos A,pirimiphos M, propaphos, prothiophos, prothoate, pyraclophos,pyridaphenthion, quinalphos, salithion, sebufos, sulfotep, sulprofos,tetrachlorvinphos, temephos, thiomethon, thionazine, trichlorfon,triazophos, vamidothion,

buprofezin, chlorfluazuron, diflubenzuron, flucycloxuron, flufenoxuron,hexaflumuron, pyriproxifen, tebufenozide, teflubenzuron, triflumuron,

imidacloprid, nitenpyram,N-[(6-chloro-3-pyridinyl)methyl]-N′-cyano-N-methylethane-imide-amide(NI-25),

abamectin, amitrazine, avermectin, azadirachtin, bensultap, Bacillusthuringiensis, cyromazine, diafenthiuron, emamectin, ethofenprox,fenpyrad, fipronil, flufenprox, lufenuron, metaldehyde, milbemectin,pymetrozine, tebufenpyrad, triazuron,

aldicarb, bendiocarb, benfuracarb, carbofuran, carbosulfan,chlorethoxyfos, cloethocarb, disulfoton, ethophrophos, etrimphos,fenamiphos, fipronil, fonofos, fosthiazate, furathiocarb, HCH,isazophos, isofenphos, methiocarb, monocrotophos, nitenpyram, oxamyl,phorate, phoxim, prothiofos, pyrachlofos, sebufos, silafluofen,tebupirimiphos, tefluthrin, terbufos, thiodicarb, thiafenox,

azocyclotin, butylpyridaben, clofentezine, cyhexatin, diafenthiuron,diethion, emaanectin, fenazaquin, fenbutatin oxide, fenothiocarb,fenpropathrin, fenypyrad, fenpyroximate, fluazinam, fluazuron,flucycloxuron, flufenoxuron, fluvalinate, fubfenprox, hexythiazox,ivemectin, methidathion, monocrotophos, moxidectin, naled, phosalone,profenofos, pyraclofos, pyridaben, pyrimidifen, tebufenpyrad,thuringiensin, triarathene and 4-bromo-2-(4-chlorophenyl)-1-(ethoxymethyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile(AC 303630).

The active compounds according to the invention can furthermore bepresent in their commercially available formulations and in the useforms, prepared from these formulations, as a mixture with synergisticagents. Synergistic agents are compounds which increase the action ofthe active compounds, without it being necessary for the synergisticagent added to be active itself.

The active compound content of the use forms prepared from thecommercially available formulations can vary within wide limits. Theactive compound concentration of the use forms can be from 0.0000001 to95% by weight of active compound, preferably between 0.0001 and 1% byweight.

The compounds are employed in a customary manner appropriate for the useforms.

When used against hygiene pests and pests of stored products, the activecompounds are distinguished by an excellent-residual action on wood andclay as well as a good stability to alkali.

The preparation of the compounds of the formula (I) according to theinvention will be illustrated with the aid of the following Examples:

Unless otherwise indicated, percentages are by weight.

PREPARATION EXAMPLES Example 1

(Process Variant a)

15.5 g (0.05 mol) of5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-methyl-pyrazole aredissolved in 120 ml of absolute dichloromethane, and 4.35 g (0.055 mol)of absolute pyridine are added. The mixture is then cooled to 0°-5° C.,and 7.3 g (0.055 mol) of 1,1-difluoroethylsulphenyl chloride are addeddropwise. The mixture is stirred for 3 hours at 0° C. and then overnightat room temperature. The mixture is subsequently washed twice with waterand dried using magnesium sulphate, and the solvent is stripped off invacuo.

13.1 g (65% of theory) of5-amino-3-methyl-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleof melting point 123°-125° C. are obtained.

Example 2

(Process Variant b)

4.6 g (0.0113 mol) of5-amino-3-methyl-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleare introduced into 30 ml of 80% strength sulphuric acid in the courseof approximately 10 minutes at 25° C.-35° C. 1 ml of 35% strength H₂O₂solution is added dropwise with cooling, and stirring is subsequentlycontinued for 20 hours at room temperature. The reaction mixture is thendiluted with water, and the precipitate is filtered off with suction.After stirring with petroleum ether, 1.8 g (38% of theory) of5-amino-3-methyl-4-(1,1-difluoroethylsulphinyl)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleof melting point 177°-179° C. are obtained.

Example 3

(Process Variant b)

2 g (0.005 mol) of5-amino-3-cyano-4-(2,2,2-trifluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleare dissolved in 10 ml of acetic acid, and a spatula-tip full of sodiumtungstate is added. 6 g (0.052 mol) of 30% strength H₂O₂ solution areadded dropwise to this solution at room temperature. Stirring iscontinued for 18 hours. Since a thin-layer chromatogram revealed thatthe reaction was still incomplete, a further 6 g (0.052 mol) of 30%strength H₂O₂ solution are added, and the mixture is stirred for afurther 18 hours at room temperature. The reaction mixture is thendiluted with approximately 100 ml of water and extracted usingdichloromethane. The dichloromethane phase is dried over magnesiumsulphate and evaporated in vacuo using a rotary evaporator.

1 g (47% of theory) of5-amino-3-cyano-4-(2,2,2-trifluoroethylsulphonyl)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleof melting point 157° C. is obtained.

The following end products of the formula (I)

can be obtained analogously to Preparation Examples 1, 2 and 3 and inaccordance with the abovementioned process (a) or (b):

TABLE 2 Ex. Physical No. R¹ R² R³ n Ar constants 4 —CH₂OCH₃ —CF₂CH₃ NH₂0

¹H-NMR δ*) = (8.2(s, 2H); 6.2(s, NH₂); 4.3(s, 2H); 3.25(s, 3H); 1.88(t,3H)) 5 CN —CF₂CH₃ NH₂ 0

m.p.: 166° C. 6 H —CF₂CH₃ NH₂ 0

m.p.: 68-69° C. 7 —CH₂OCH₃ —CF₂CH₃ NH₂ 0

¹H-NMR δ**) = (8.99(d, 1H); 8.78 (d, 1H); 6.3(bs, NH₂); 4.3(s, 2H);3.21(s, 3H); 1.90(t, 3H)) 8 CH₃ —CF₂CH₃ NH₂ 0

¹H-NMR δ*) = (8.6(d, 1H); 8.15 (d, 1H); 5.5(bs, NH₂); 2.3(s, 3H); 1.9(t,3H)) 9 CH₃ —CF₃CH₃ NH₂ 2

¹H-NMR δ**) = (9.05(d, 1H); 8.82 (d, 1H); 6.89(bs, NH₂); 2.20 (s, 3H);2.02(t,3H)) 10 CH₃ —CF₂CH₃ NH₂ 2

¹H-NMR δ*) = (7.68(bs); 7.49(d); 4.28(bs, NH₂); 2.3(s, CH₃); 1.9 (t,3H)) 11 —CH₂OCH₃ —CF₂CH₃ NH₂ 0

^(:)H-NMR δ** = ) = (8.05(m, 2H); 6.25 (bs, NH₂); 4.3(m, 2H); 3.22(s,3H); 1.89(t, 3H)) 12 CH₃ —CF₂CH₃ NH₂ 0

¹H-NMR δ**) = (8.03(m, 2H); 6.15 (bs, NH₂); 2.1(s, 3H); 1.85(t, 3H)) 13—CH₂OCH₃ —CH₂CF₃ NH₂ 0

m.p.: 77° C. 14 —CN —CH₂CF₃ NH₂ 0

¹H-NMR δ**) = (7.8(s, 2H); 6.12 (bs, NH₂); 3.4(q, 2H)) 15 —CH₃ —CH₂CF₃NH₂ 0

m.p.: 126-128° C. 16 —CH₂OCH₃ —CH₂CF₃ NH₂ 0

¹H-NMR δ**) = (8.95(d, 1H); 8.75 (d, 1H); 6.12(bs, NH₂); 4.32(s, 2H);3.45(q, 2H); 3.28(s, 3H)) 17 —CH₃ —CH₂CF₃ NR₂ 0

m.p.: 36° C. 18 H —CH₂CF₃ NH₂ 0

m.p.: 90-92° C. 19 —CH₂OCH₃ —CH₂CF₃ NH₂ 1

wax 20 H —CH₂CF₃ NH₂ 1

m.p.: 134-136° C. 21 CH₃ —CH₂CF₃ NH₁ 1

m.p.: 104-105° C. 22 —CN —CF₂CH₃ NH₂ 2

m.p.: 163° C. 23 —CH₂OCH₃ —CH₂CF₃ NH₂ 2

¹H-NMR δ**) = (9.04(d, 1H); 8.85 (d, 1H); 6.71(bs, NH₂); 4.61(q, 2H);4.40(s, 2H); 3.30(s, 3H)) 24 —CH₂OCH₃ —CH₂CF₃ NH₂ 2

25 CH₃ —CH₂CF₃ NH₂ 2

m.p.: 160° C. 26 CH₂Br —CF₂CH₃ NH₂ 0

m.p.: 160° C. 27 —C(CH₃)₃ —CF₂CH₃ NH₂ 0

m.p.: 117° C.

Example 28

(Process Variant c)

2 g (0.005 mol) of5-amino-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-methoxymethylpyrazoleare dissolved in 20 ml of anhydrous toluene, and 2 g (0.025 mol) ofanhydrous pyridine are added. 0.8 g (0.007 mol) of methoxyacetylchloride are added dropwise in the course of 5 minutes, and stirring issubsequently continued for 12 hours at 80° C. For working-up, themixture is diluted with water, and the organic phase is separated offand dried over magnesium sulphate and concentrated in vacuo. 1.4 g (60%of theory) of5-methoxymethyl-carbonylamino)-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethyl-phenyl)-3-methoxymethylpyrazoleremain as a brown wax.

¹H-NMR δ*)=(10.3 ppm (1H); 8.2 ppm (2H); 4.48 ppm (2H); 3.9 ppm (2H);3.29 ppm (3H); 3.18 ppm (3H); 1.89 ppm (3H)).

Example 29

(Process Variant d)

0.4 g (0.001 mol) of5-amino-3-cyano-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)pyrazolein 2 g (0.017 mol) of dimethylformamide dimethyl acetal is heated for 18hours at 130° C. and subsequently evaporated in vacuo on a rotaryevaporator.

0.4 g (89% of theory) of5-(N,N-dimethylaminomethylideneamino)-3-cyano-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleis obtained as an orange oil of boiling point 220° C./0.01 mm.

Example 30

(Process Variant e)

5.88 g (0.015 mol) of5-amino-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleare dissolved in 100 ml of toluene, 2.2 g (0.0165 mol) of2,5-dimethoxytetrahydrofuran and a spatula-tip full ofp-toluenesulphonic acid are added, and the mixture is heated for 20hours on a water separator. The solvent is stripped off in vacuo, andthe residue which remains is stirred with ligroin and filtered off withsuction.

4.6 g (69% of theory) of4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-5-(pyrrol-1-yl)pyrazoleare obtained.

Example 31

(Process Variant f)

5 g (12.3 mmol) of5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-methyl-4-(1,1-difluoroethylthio)-pyrazoleand 5 g (32.9 mmol) of 3-methoxy-4-hydroxybenzaldehyde are treated with4 g of molecular sieve Baylith SV 133 in the absence of a solvent andthe mixture is stired for 18 hours at an oil-bath temperature of 140° C.For working-up, the mixture is dissolved in methylene chloride, and themolecular sieve is removed by filtration. The filtrate is concentratedin vacuo, and the excess of vanillin is removed by distillation (up to140° C./0.1 mm). The brown residue is taken up in ethanol and filteredthrough 100 g of silica gel 60. After evaporation of the solvent, 2.4 g(36% of theory) of5-(4-hydroxy-3-methoxybenzylideneamino)-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-methyl-4-(1,1-difluoroethylthio)-pyrazoleremain as a shiny brown solid of melting point 67° C.

Example 32

(Process Variant h)

5.88 g (0.015 mol) of5-amino-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleare dissolved in 50 ml of bromoform. 4.64 g (0.045 mol) of tert-butylnitrite are added dropwise at 80° C. and stirring is subsequentlycontinued for 1 hour at 80° C. The solvent is then stripped off invacuo.

3.7 g (54% of theory) of5-bromo-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleare obtained. ¹H-NMR δ*)=7.8 ppm (s, 2H); 7.75 ppm (s, 1H); 1.95 ppm (t,3H).

Example 33

(Process Variant i)

5.88 g (0.015 mol) of5-amino-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleare dissolved in 100 ml of dioxane and refluxed for 24 hours with 1.5 g(0.03 mol) of hydrazine hydrate. After this, a further 1.5 g (0.03 mol)of hydrazine hydrate are added, and refluxing is continued for 24 hours.The solvent is then stripped off in vacuo, the residue is taken up inwater, and the mixture is extracted using dichloromethane.

After the dichloromethane has been distilled off in vacuo, 4.1 g (71% oftheory) of5-amino-4-(1,1-difluoroethylthio)-1-(2-chloro-4-trifluoromethyl-6-hydrazinophenyl)-pyrazoleof melting point 98°-99° C. are obtained.

Example 34

(Process Variant i)

1.3 g (0.003 mol) of5-amino-3-cyano-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleand 0.4 g (0.007 mol) of sodium methylate are refluxed for 6 hours in 20ml of dry methanol. After this, a further 0.3 g (0.005 mol) of sodiummethylate are added, and refluxing is continued for 10 hours. After thesolvent has been stripped off in vacuo, the residue which remains isstirred with water and subjected to filtration with suction. Theprecipitate is washed repeatedly with water and dried.

1.1 g (85% of theory) of5-amino-3-cyano-4-(1,1-difluoroethylthio)-1-(2-chloro-4-trifluoromethyl-6-methoxyphenyl)-pyrazoleof melting point 79° C. are obtained.

Example 35

0.7 g (1.7 mmol) of5-amino-1-(2-chloro-6-fluoro-4-trifluoromethylphenyl)-3-methoxymethyl-4-(1,1-difluoroethylthio)-pyrazoleand 1 g (6.54 mmol) of tetraethylammonium cyanide are dissolved in 5 mlof anhydrous dimethylformamide and the mixture is stirred for 18 hoursat approximately 100°-110° C. For working-up, the mixture is poured into100 ml of water, and the solid obtained is filtered off with suction.After the product has been washed repeatedly with water, 0.45 g (63% oftheory) of5-amino-1-(2-chloro-6-cyano-4-trifluoromethyl)-3-methoxymethyl-4-(1,1-difluoroethylthio)-pyrazoleis obtained as an ochre solid of melting point 84° C.

Example 36

18 ml of water and 18 ml of concentrated sulphuric acid are added at 0°C. to 9 g (0.022 mol) of5-amino-1-(2-chloro-4-trifluoromethylpyridyl)-3-methoxymethyl-4-(1,1-difluoroethylthio)-pyrazole.A solution of 2.3 g (0.033 mol) of sodium nitrite and 10 ml of water isadded dropwise at 0° C. in the course of approximately 30 minutes. After0.5 g of urea have been added, 27 ml (0.261 mol) of hypophosphorous acid(50% strength aqueous solution) are added dropwise at 0° C. Stirring isthen continued for 18 hours at room temperature. After the addition ofpotassium carbonate, the alkaline solution is extracted usingdichloromethane. The combined dichloromethane phases are dried overMgSO₄ and then concentrated in vacuo. The oil which remains is thendistilled using a bulb tube. At 180° C./0.1 mm, 4.2 g (48% of theory) of1-(2-chloro-4-trifluoromethylpyridyl)-3-methoxymethyl-4-(1,1,1-difluoroethylthio)-pyrazoleare obtained as an orange oil.

The following end products of the formula (I) can be obtainedanalogously to Preparation Examples 28 to 36 and in accordance with theabovementioned processes (c), (d), (e), (f), (g), (h) and (i):

TABLE 3 (I)

Ex. Physical No. R¹ R² R³ n Ar constants 37 H —CF₂CH₃ NH₂ 0

38 CH₃ —CF₂CH₃ NH₂ 0

m.p.: 131-133° C. 39 —CN —CF₂CH₃ —N═CH—N(CH₃)₂ 0

40 CH₃ —CF₂CH₃

0

41 CH₃ —CF₂CH₃ Br 0

42 H —CF₂CH₃ NH₂ 0

43 CH₃ —CF₂CH₃ NH₂ 0

m.p.: 135-138° C. 44 —CH₂OCH₃ —CF₂CH₃ NH₂ 0

Resin 45 —CH₂OCH₃ —CF₃ NH₂ 0

46 —CH₂OCH₃ —CF₂CH₃ NH₂ 0

47 —CH₃ —CF₂CH₃

0

m.p.: 90° C. 48 —CH₃ —CF₂CH₃

0

Wax

Preparation of the Starting Compounds Example (II-1)

37 g (151 mmol) of 2,6-dichloro-4-trifluoromethylphenylhydrazine and 4.9g (438 mmol) of 1-cyano-2-amino-3-methoxy-propene are refluxed for 24hours in 300 ml of ethanol and 20 ml of acetic acid. After this, afurther 12 g (49 mmol) of 2,6-dichloro-4-trifluoromethylphenylhydrazineare added, and refluxing is continued for 24 hours. The solvent issubsequently stripped off in vacuo, and the residue is purified bycolumn chromatography (silica gel; eluent: cyclohexane/ethyl ester 1:1).

48.4 g (71% of theory) of5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-methoxy-methyl-pyrazoleare obtained as an oil.

¹H-NMR δ*)=7.7 ppm (s, 2H); 5.74 ppm (s, 1H); 4.42 ppm (s, 2H); 3.4 ppm(s, 3H).

A solution of 15 g (0.21 mol) of methoxyacetonitrile and 10 g (0.24 mol)of acetonitrile in 50 ml of dry tetrahydrofuran is added dropwise in thecourse of approximately 30 minutes to 21.5 g (0.19 mol) of potassiumtert-butylate in 250 ml of dry tetrahydrofuran. After the addition hasended, the mixture is refluxed for a further 24 hours. After carefullyhydrolysing with water, the mixture is extracted with dichloromethane.The combined organic phases are dried over magnesium sulphate and thenconcentrated in vacuo. Subsequent fractional distillation at 80° C./0.2mm gives 8.9 g (38% of theory) of 2-amino-1-cyano-3-methoxypropene as anorange oil.

The ¹³C-NMR data reveal that the ratio of the E/Z isomers is 1:4.

Example (II-2)

Analogously,5-amino-1-(2-chloro-6-fluoro-4-trifluoromethylphenyl)-3-methoxymethylpyrazoleis obtained from 2-chloro-6-fluoro-4-trifluoromethylphenyl-hydrazine and2-amino-1-cyano-3-methoxy-propene.

Example (II-3)

Analogously,5-amino-1-(2-chloro-4-trifluoromethylpyridyl)-3-methoxymethyl-pyrazoleis obtained as an oil from 2-chloro-4-trifluoromethylpyridyl-hydrazineand 2-amino-1-cyano-3-methoxypropene.

¹H-NMR δ*)=8.6 ppm (d, 1H); 8.13 ppm (d, 1H); 5.67 ppm (s, 1H); 4.8 ppm(bs, NH₂); 4.41 ppm (s, 2H); 3.4 ppm (s, 3H).

Example (II-4)

1.5 g (4.4 mmol) of5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-methoxymethyl-pyrazoleare heated for approximately 8 hours at 120°-130° C. in a mixture of 30ml of 48% strength HBr and 15 ml of acetic acid. The reaction mixture isconcentrated in vacuo and then stirred with dilute ammonia solution. Thebrown solid is filtered off with suction and repeatedly washed withwater.

1.6 g (93% of theory) of5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-bromomethylpyrazoleof melting point 220° C. are obtained.

Example (II-5)

Analogously,5-amino-1-(2-chloro-4-trifluoromethylpyridyl)-3-bromomethyl-pyrazole isobtained from5-amino-1-(2-chloro-4-trifluoromethylpyridyl)-3-methoxymethylpyrazole,48% strength HBr solution and acetic acid.

Example (II-6)

5 g (12.9 mmol) of5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-bromomethyl-pyrazoleand 2.5 g (51 mmol) of sodium cyanide in 30 ml of water are stirred for18 hours at 90° C. in the presence of 4 g (17.6 mmol) oftriethylbenzylammonium chloride. The mixture is cooled to approximately5° C., and the grey solid is filtered off with suction. Chromatographyon silica gel 60 (eluent:methylene chloride/ethanol 1:1) gives 1.7 g(40% of theory) of5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl-3-cyanomethyl-pyrazoleas a brown solid of melting point 98° C.

*) The ¹H-NMR spectra were recorded in deuterochloroform (CDCl₃) usingtetramethylsilane (TMS) as the internal standard. The data given is thechemical shift as δ value in ppm.

**) The ¹H-NMR spectra were recorded in deuterated dimethyl sulphoxide(CDCl₃)₂SO) with tetramethylsilane (TMS) as the internal standard. Thedata given is the chemical shift as 6 value in ppm.

Use Examples

In the Use Examples which follow, the compound given below is employedas comparison substance:

5-Amino-1-[2,6-dichloro-4-(trifluoromethyl)-phenyl]-4-[(trimethyl)-sulphinyl]-3-cyano-1H-pyrazole (disclosed in EP-A 295 117)

Example A

Myzus Test

Solvent: 7 parts by weight of dimethylformamide

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weightof active compound is mixed with the stated amount of solvent and thestated amount of emulsifier, and the concentrate is diluted with waterto the desired concentration.

Cabbage leaves (Brassica oleracea) which are heavily infested with thepeach aphid (Myzus persicae) are treated by being dipped into thepreparation of active compound of the desired concentration.

After the specified period of time, the destruction in % is determined.100% means that all the aphids have been killed; 0% means that none ofthe aphids have been killed.

In this test, a superior activity compared with the prior art (degree ofdestruction 0%) is shown, for example, by the compounds of PreparationExamples 1, 6 and 18 with a degree of destruction of between 98% and100% at a Concentration of active compound of 0.1% after one day.

Example B

Aphis Test (Systemic Action)

Solvent: 7 parts by weight of dimethylformamide

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weightof active compound is mixed with the stated amount of solvent and thestated amount of emulsifier, and the concentrate is diluted with waterto the desired concentration.

Bean plants (Vicia faba) which are heavily infested with the black beanaphid (Aphis fabae) are each watered with 20 ml of preparation of activecompound of the desired concentration in such a way that the preparationof active compound penetrates into the soil without wetting the shoot.The active compound is taken up by the roots and passes to the shoot.

After the specified period of time, the destruction in % is determined.100% means that all the aphids have been killed; 0% means that none ofthe aphids have been killed.

In this test, a superior activity compared with-the prior art (degree ofdestruction 0%) is shown, for example, by the compounds of PreparationExamples 1, 6, 18, 21 and 33 with a degree of destruction of between 90%and 100% at a concentration of active compound of 0.02% after four days.

Example C

Critical Concentration Test/Root-Systemic Action.

Test insect: Phaedon cochleariae larvae

Solvent: 3 parts by weight of acetone

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weightof active compound is mixed with the stated amount of solvent, thestated amount of emulsifier is added and the concentrate is diluted withwater to the desired concentration.

The preparation of active compound is intimately mixed with soil. Theconcentration of the active compound in the preparation is ofpractically no importance, only the amount by weight of active compoundper unit volume of soil, which is given in ppm (=mg/l), being decisive.The treated soil is transferred into pots and these are planted withcabbage (Brassica oleracea). The active compound can in this way betaken up from the soil by the roots of the plants and be transferredinto the leaves.

To demonstrate the root-systemic effect, exclusively the leaves areinfested with the abovementioned test animals after 7 days. After afurther 2 days, the evaluation is made by counting or estimating thedead animals. The root-systemic action of the active compound is deducedfrom the mortality figures. It is 100% if all test animals have beenkilled and 0% if just as many test insects are still alive as in thecase of the untreated control.

In this test, a superior activity compared with the prior art (degree ofdestruction 0%) is shown, for example, by the compounds of PreparationExamples 1, 6, 15, 25, 33, 37 and 38 with a degree of destruction of ineach case 100% at a concentration of active compound of 2.5 ppm.

Example D

Critical Concentration Test/Root-Systemic Action

Test insect: Myzus persicae

Solvent: 3 parts by weight of acetone

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weightof active compound is mixed with the stated amount of solvent, thestated amount of emulsifier is added and the concentrate is diluted withwater to the desired concentration.

The preparation of active compound is intimately mixed with soil. Theconcentration of the active compound in the preparation is ofpractically no importance, only the amount by weight of active compoundper unit volume of soil, which is given in ppm (=mg/l), being decisive.The treated soil is transferred into pots and these are planted withcabbage (Brassica oleracea). The active compound can in this way betaken up from the soil by the roots of the plants and be transferredinto the leaves.

To demonstrate the root-systemic effect, exclusively the leaves areinfested with the abovementioned test animals after 7 days. After afurther 2 days, the evaluation is made by counting or estimating thedead animals. The root-systemic action of the active compound is deducedfrom the mortality figures. It is 100% if all test animals have beenkilled and 0% if just as many test insects are still alive as in thecase of the untreated control.

In this test, a degree of destruction of 100% compared with the priorart (degree-of destruction 0%) is shown, for example, by the compound ofPreparation Example 6 at a concentration of active compound of 20 ppm.

Example E

Blowfly Larvae Test

Test animals: Lucilia cuprina larvae

Emulsifier:

35 parts by weight of ethylene glcyol monomethyl ether

35 parts by weight of nonylphenol polyglycol ether

To produce a suitable preparation of active compound, three parts byweight of active compound are mixed with seven parts by weight of theabovementioned mixture and the emulsion concentrate thus obtained isdiluted with water to the particular desired concentration.

About 20 Lucilia cuprina res. larvae are introduced into a test tubewhich contains approx. 1 cm³ of horse meat and 0.5 ml of the preparationof active compound. After 24 hours, the effectiveness of the preparationof active compound is determined. 100% means that all blowfly larvaehave been killed; 0% means that none of the blowfly larvae have beenkilled.

In this test, a destructive activity of 100%. is shown, for example, bythe compounds of Preparation Examples 5, 14, 18, 20, 22, 28 and 33 at aconcentration of active compound of ≧300 ppm, compared with the priorart where this activity is only achieved at a concentration of activecompound of 1000 ppm.

Example F

Fly Test

Test animals: Musca domestica, strain WHO (N)

Solvent:

35 parts by weight of ethylene glycol monomethyl ether

35 parts by weight of nonylphenol polyglycol ether

To produce a suitable formulation, three parts by weight of activecompound are mixed with seven parts of the abovementionedsolvent/emulsifier mixture, and the emulsion concentrate thus obtainedis diluted with water to the particular desired concentration.

2 ml of this preparation of active compound are pipetted onto filterpaper discs (φ9.5 cm) located in Petri dishes of a suitable size. Afterthe filter paper discs have dried, 25 test animals are introduced intothe Petri dish, which is covered.

After 6 hours, the effectiveness of the preparation of active compoundis determined. The effectiveness is expressed in %. 100% means that allflies have been killed; 0% means that none of the flies have beenkilled.

In this test, a superior activity (100% destruction) compared with theprior art (<100%) is shown, for example, by the compound of PreparationExample (6) at a concentration of active compound of 1 ppm.

Example G

Cockroach Test

Test animals: Blattella germanica or Periplaneta americana

Solvent:

35 parts by weight of ethylene glycol monomethyl ether

35 parts by weight of nonylphenol polyglycol ether

To produce a suitable formulation, three parts by weight of activecompound are mixed with seven parts of the abovementionedsolvent/emulsifier mixture, and the emulsion concentrate thus obtainedis diluted with water to the particular desired concentration.

2 ml of this preparation of active compound are pipetted onto filterpaper discs (φ9.5 cm) located in Petri dishes of a suitable size. Afterthe filter paper discs have dried, 5 test animals (Blattella germanicaor Periplaneta americana) are introduced into the Petri dish, which iscovered.

After 6 hours, the effectiveness of the preparation of active compoundis determined. The effectiveness is expressed in %. 100% means that allcockroaches have been killed; 0% means that none of the cockroaches havebeen killed.

In this test, a superior activity (100% destruction at a concentrationof active compound of >10 ppm) compared with the prior art (degree ofdestruction <100% at a concentration of active compound of 10 ppm) isshown, for example, by the compound of Preparation Example (1).

Example H

Flea In-Vitro Test (All Development Stages)

Test subject: All stages (eggs, larvae, pupae and adults) ofCtenocephalides felis.

Test procedure:

Blood meal is dried overnight in a shallow dish at approximately 70° C.and then screened using a mesh size of 0.63 mm.

1.8 g portions of this prepared blood meal are transferred into plasticPetri dishes of φ9.8 cm.

Using an Eppendorf pipette, 0.2 ml of substance are placed on the 1.8 gof blood meal (dilution factor 1:10).

That is to say, at a use concentration of 1 ppm, the aqueous solutionmust have a concentration of 10 ppm. The solution is distributeddropwise over the entire surface of-the blood meal.

These prepared dishes are allowed to dry overnight. Using a suitabledevice, the substance, which is now in the form of dried lumps of bloodmeal, is crushed and distributed uniformly in the Petri dish by rotatingmovements. A spatula-full of sieved flea eggs (which are obtained fromartificially infected cats) is now added to these prepared test dishes.The dish is sealed with Parafilm and shaken vigorously.

Incubation is effected at 25° C. and the relative atmospheric humidityof 85%. At certain intervals, the dishes are examined for developmentstages of fleas.

Test criteria: The criteria used for the in-vitro activity of asubstance is the inhibition of flea development or a standstill of thedevelopment before the adult stage is reached.

Evaluation:

Effective: No adult fleas after 1½ times the development time.

Ineffective: Adult fleas after 1½ times the development time.

In this test, a clearly superior activity (destruction of 100% at anactive compound concentration of as little as 1 ppm) compared with theprior art (0% destruction at an active compound concentration of 10%) isshown, for example, by the compound of Preparation Example (5).

It will be understood that the specification and examples areillustrative but not limitative of the present invention and that otherembodiments within the spirit and scope of the invention will suggestthemselves to those skilled in the art.

What is claimed is:
 1. A substituted 1-arylpyrazole of the formula

wherein R¹ represents hydrogen, cyano, alkyl, alkoxyalkyl,alkylthioalkyl, halogenoalkyl or cyanoalkyl, R² represents difluoroethylor trifluoroethyl, R³ represents hydrogen, amino, halogen or one of thefollowing groups

in which R⁴ represents alkyl, halogenoalkyl, alkoxyalkyl or optionallysubstituted phenyl, R⁵ represents hydrogen or alkyl, R⁶ representshydrogen, alkyl or optionally substituted phenyl, and R⁷ representsalkyl, or R⁵ and R⁶ together with the carbon atom to which they arebonded represent an optionally substituted heterocycle, Ar representsoptionally substituted pyridyl, and n represents a number 0, 1 or
 2. 2.A substituted 1-arylpyrazole according to claim 1, wherein R¹ representshydrogen, cyano, (C₁-C₆)-alkyl, (C₁-C₄)-alkoxy-(C₁-C₄)-alkyl,(C₁-C₄)-halogenoalkyl or (C₁-C₂)-cyanoalkyl, R² represents difluoroethylor trifluoroethyl, R³ represents hydrogen, amino, halogen or one of thefollowing groups

wherein R⁴ represents (C₁-C₆)-alkyl, (C₁-C₆)-halogenoalkyl having 1-3halogen atoms, (C₁-C₆)-alkoxy-(C₁-C₆)-alkyl, or phenyl which isoptionally monosubstituted to trisubstituted by identical or differentsubstituents, R⁵ represents hydrogen or (C₁-C₆)-alkyl, R⁶ representshydrogen, (C₁-C₆)-alkyl, or phenyl which is optionally monosubstitutedto trisubstituted by identical or different substituents, R⁷ represents(C₁-C₆)-alkyl or R⁵ and R⁶ together with the carbon atom to which theyare bonded represent optionally substituted pyridyl, Ar representspyridyl optionally monosubstituted to trisubstituted by identical ordifferent substituents selected from the series comprising groupconsisting of halogen, halogeno (C₁-C₆)alkyl, halogeno(C₁-C₆)alkylthio,halogeno(C₁-C₆)alkoxy, alkoxy, hydrazino, (C₁-C₆)-dialkylhydrazino,amino, amino (C₁-C₆)alkyl, diamino(C₁-C₆)alkyl, imino(C₁-C₆)alkyl,cyano, (C₁-C₆)alkylthio or and the group

in which R⁹ and R¹⁰ are identical or different and represent hydrogen or(C₁-C₆)-alkyl, and n represents a number 0, 1 or
 2. 3. A substituted1-arylpyrazole according to claim 1, wherein R¹ represents hydrogen,cyano, (C₁-C₄)-alkyl, (C₁-C₄)-alkoxy-(C₁-C₂)-alkyl,(C₁-C₂)-halogenoalkyl having 1 to 5 identical or different fluorine,chlorine or bromine atoms, or cyanomethyl, R² represents difluoroethylor trifluoroethyl, R³ represents hydrogen, amino, bromine or one of thefollowing groups

wherein R⁴ represents (C₁-C₄)-alkyl, (C₁-C₄)-halogenoalkyl having 1-3halogen atoms, (C₁-C₄)-alkoxy-(C₁-C₂)alkyl, or phenyl which isoptionally monosubstituted to trisubstituted by identical or differentsubstituents, R⁵ represents hydrogen or (C₁-C₄)-alkyl, R⁶ representshydrogen, (C₁-C₄)-alkyl, phenyl which is optionally monosubstituted ordisubstituted by identical or different substituents, or4-hydroxy-3-methoxy-phenyl, R⁷ represents (C₁-C₄)-alkyl, or R⁵ and R⁶together with the carbon atom to which they are bonded representoptionally substituted pyridyl, Ar represents pyridyl optionallymonosubstituted to trisubstituted by identical or different substituentsselected from the series comprising group consisting of fluorine,chlorine, trifluoromethyl, trifluoromethylthio, trifluoromethoxy,methoxy, hydrazino, dimethylhydrazino, amino, methylamino,dimethylamino, iminomethyl, cyano, methylthio or and the group

in which R⁹ and R¹⁰ are identical or different and represent hydrogen or(C₁-C₄)-alkyl, and n represents a number 0, 1 or
 2. 4. A substituted1-arylpyrazole according to claim 1, wherein R¹ represents hydrogen,cyano, (C₁-C₄)-alkyl, methoxymethyl, ethoxymethyl, methoxyethyl,ethoxyethyl, trifluoromethyl, bromomethyl and cyanomethyl, R² represents1,1-difluoroethyl or 2,2,2-trifluoroethyl, R³ represents halogen, amino,bromine or one of the following groups

wherein R⁴ represents (C₁-C₄)-alkyl, (C₁-C₄)-halogenoalkyl having 1-3halogen atoms, (C₁-C₄)-alkoxy-(C₁-C₂)alkyl, or phenyl which isoptionally monosubstituted to trisubstituted by identical or differentsubstituents, R⁵ represents hydrogen or (C₁-C₄)-alkyl, R⁶ representshydrogen, (C₁-C₄)-alkyl, phenyl which is optionally monosubstituted ordisubstituted by identical or different substituents, or4-hydroxy-3-methoxy-phenyl, R⁷ represents (C₁-C₄)-alkyl, or R⁵ and R⁶together with the carbon atom to which they are bonded representoptionally substituted pyridyl, Ar represents a 2-pyridyl radical whichis substituted in the 4-position by trifluoromethyl and in the6-position by fluorine or chlorine, and n represents a number 0, 1 or 2.5. A compound according to claim 1, wherein R³ is amino.
 6. A compoundaccording to claim 1, wherein Ar represents a 2-pyridyl radical which issubstituted in the 4-position by trifluoromethyl and in the 6-positionby fluorine or chlorine.
 7. A compound according to claim 1, whereinsuch compound is5-amino-3-methyl-4-(1,1-difluoroethylthio)-1-(3-chloro-5-trifluoromethlpyrid-2-yl)-pyrazoleof the formula


8. An insecticidal composition comprising an insecticidally effectiveamount of a compound according to claim 1 and a diluent.
 9. A method ofcombating unwanted insects which comprises administering to such insectsor to a locus from which it is desired to exclude such insects aninsecticidally effective amount of a compound according to claim
 1. 10.A substituted 1-arylpyrazole of the formula

wherein n represents 0, 1 or 2 R¹ represents hydrogen, cyano, alkyl,alkoxyalkyl, alkylthioalkyl, halogenoalkyl or cyanoalkyl, R² representsdifluoroethyl or trifluoroethyl, R³ represents hydrogen, amino, halogenor one of the following groups

in which R⁴ represents alkyl, halogenoalkyl, alkoxyalkyl or optionallysubstituted phenyl, R⁵ represents hydrogen or alkyl, R⁶ representshydrogen, alkyl or optionally substituted phenyl, and R⁷ representsalkyl, or R⁵ and R⁶ together with the carbon atom to which they arebonded represent an optionally substituted heterocycle, Ar representsphenyl which is trisubstituted by identical or different substituents,substituents in the 2-, 4 - and 6 -positions, substituents in the2-position being fluorine or chlorine, in the 4-position trifluoromethyland in the 6-position fluorine or chlorine.
 11. A compound according toclaim 10, wherein R¹ represents hydrogen, cyano, (C₁-C₆)-alkyl,(C₁-C₄)-alkoxy-(C₁-C₄)-alkyl, (C₁-C₄)-halogenoalkyl or(C₁-C₂)-cyanoalkyl, R² represents difluoroethyl or trifluoroethyl, R³represents hydrogen, amino, halogen or one of the following groups

wherein R⁴ represents (C₁-C₆)-alkyl, (C₁-C₆)-halogenoalkyl having 1-3halogen atoms, (C₁-C₆)-alkoxy-(C₁-C₆)-alkyl, or phenyl which isoptionally monosubstituted to trisubstituted by identical or differentsubstituents, R⁵ represents hydrogen or (C₁-C₆)-alkyl, R⁶ representshydrogen, (C₁-C₆)-alkyl, or phenyl which is optionally monosubstitutedto trisubstituted by identical or different substituents, R⁷ represents(C₁-C₆)-alkyl or R⁵ and R⁶ together with the carbon atom to which theyare bonded represent optionally substituted pyridyl.
 12. A compoundaccording to claim 10, wherein R³ is amino.
 13. A compound according toclaim 10, wherein such compound is5-amino-3-methyl-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazole of the formula


14. A compound according to claim 10, wherein such compound is5-amino-3-cyano-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazole of the formula


15. A compound according to claim 10, wherein such compound is5-amino-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazoleof the formula


16. A compound according to claim 10, wherein such compound is5-amino-3-cyano-4-(1,1-difluoroethylthio))-1-(2,4,6-trichlorophenyl)-pyrazoleof the formula

5-amino- 3 -cyano- 4 -( 1,1 -difluoroethylsulfonyl)- 1 -( 2,6 -dichloro-4 -trifluoromethylphenyl)-pyrazole of the formula


17. An insecticidal composition comprising an insecticidally effectiveamount of a compound according to claim 10 and a diluent.
 18. A methodof combating unwanted insects which comprises administering to suchinsects or to a locus from which it is desired to exclude such insectsan insecticidally effective amount of a compound according to claim 10.19. The method according to claim 18 wherein such compound is5-amino-3-methyl-4-(1,1-difluorothylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazole,5-amino-3-cyano-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazole,5-amino-4-(1,1-difluoroethylthio)-1-(2,6-dichloro-4-trifluoromethylphenyl)-pyrazole,or5-amino-3-cyano-4-(1,1-difluoroethylthio))-1-(2,4,6-trichlorophenyl)-pyrazole.20. A compound according to claim 10, of the formula